1. Field of the Invention
The present invention relates to an InfiniBand(trademark) router configured for sending and receiving data packets on an InfiniBand(trademark) network.
2. Background Art
Networking technology has encountered improvements in server architectures and design with a goal toward providing servers that are more robust and reliable in mission critical networking applications. In particular, the use of servers for responding to client requests has resulted in a necessity that servers have an extremely high reliability to ensure that the network remains operable. Hence, there has been a substantial concern about server reliability, accessibility, and serviceability.
In addition, processors used in servers have encountered substantial improvements, where the microprocessor speed and bandwidth have exceeded the capacity of the connected input/out (I/O) buses, limiting the server throughput to the bus capacity. Accordingly, different server standards have been proposed in an attempt to improve server performance in terms of addressing, processor clustering, and high-speed I/O.
These different proposed server standards led to the development of the InfiniBand(trademark) Architecture Specification, (Release 1.0), adopted by the InfiniBand(trademark) Trade Association. The InfiniBand(trademark) Architecture Specification specifies a high-speed networking connection between central processing units, peripherals, and switches inside a server system. Hence, the term xe2x80x9cInfiniBand(trademark) networkxe2x80x9d refers to a network within a server system. The InfiniBand(trademark) Architecture Specification specifies both I/O operations and interprocessor communications (IPC).
A particular feature of InfiniBand(trademark) Architecture Specification is the proposed implementation in hardware of the transport layer services present in existing networking protocols, such as TCP/IP based protocols. The hardware-based implementation of transport layer services provides the advantage of reducing processing requirements of the central processing unit (i.e., xe2x80x9coffloadingxe2x80x9d), hence offloading the operating system of the server system.
The InfiniBand(trademark) Architecture Specification describes a network architecture, illustrated in FIG. 1. The network 10 includes nodes 11, each having an associated channel adapter 12 or 14. For example, the computing node 11a includes processors 16 and a host channel adapter (HCA) 12; the destination target nodes 11b and 11c include target channel adapters 14a and 14b, and target devices (e.g., peripherals such as Ethernet bridges or storage devices) 18a and 18b, respectively. The network 10 also includes routers 20, and InfiniBand(trademark) switches 22.
Channel adapters operate as interface devices for respective server subsystems (i.e., nodes). For example, host channel adapters (HCAs) 12 are used to provide the computing node 11a with an interface connection to the InfiniBand(trademark) network 10, and target channel adapters (TCAs) 14 are used to provide the destination target nodes 11b and 11c with an interface connection to the InfiniBand(trademark) network. Host channel adapters 12 may be connected to a memory controller 24 as illustrated in FIG. 1. Host channel adapters 12 implement the transport layer using a virtual interface referred to as the xe2x80x9cverbsxe2x80x9d layer that defines in the manner in which the processor 16 and the operating system communicate with the associated HCA 12: verbs are data structures (e.g., commands) used by application software to communicate with the HCA. Target channel adapters 14, however, lack the verbs layer, and hence communicate with their respective devices 18 according to the respective device protocol (e.g., PCI, SCSI, etc.).
Presently, when a data packet is sent from a TCP-IP network to an InfiniBand(trademark) network, there is no mapping support in the InfiniBand(trademark) network for IP priorities and the packet is simply sent by a router as a raw datagram. Thus, the IP priorities of the packet are not retained.
When an IP packet is sent from a TCP-IP network to an InfiniBand(trademark) network, there is a need to send from a router, an InfiniBand(trademark) packet according to a determined service level based on a type of service field in the IP packet.
These and other needs are attained by the present invention, where a router is configured for sending and receiving data packets on an InfiniBand(trademark) network. The router is configured to receive an Internet Protocol (IP) data packet having an IP header including a type of service (TOS) field having a differentiated services code point indicative of layer 3 priority data of the IP packet. The router includes a mapping table having multiple entries, each entry specifying a differentiated services code point and a corresponding service level. The controller is configured for parsing the TOS field and determining the service level for the differentiated services level. The controller outputs the IP packet on the InfiniBand(trademark) network within an InfiniBand(trademark) packet according to the determined services level.
Another aspect of the present invention provides a method of outputting an IP packet, received by a router, onto an InfiniBand(trademark) network. The method includes receiving, by the router, an Internet Protocol (IP) data packet having an IP header including a type of service (TOS) field specifying a differentiated services code point value. The TOS field is parsed and the differentiated services code point value is mapped to a determined service level based on the parsed TOS field. The IP packet is outputted on the InfiniBand(trademark) network within an InfiniBand(trademark) packet according to the determined service level.
Additional advantages and novel features of the invention will be set forth in part in the description which follows and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The advantages of the present invention may be realized and attained by means of instrumentalities and combinations particularly pointed in the appended claims.